Offsetting Arrangements - Assets With Enforceable Netting Arrangements (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Offsetting [Abstract]
Derivative, net amount of assets presented in statement of condition	$ 8,784	$ 4,777
Derivatives, counterparty netting	0	0
Derivatives, collateral received	(445)	(405)
Derivatives, net amount	8,339	4,372
Resale agreements and securities borrowing, resale agreements and securities borrowing, net amount of assets presented in statement of condition	22,085	23,525
Resale agreements and securities borrowing, counterparty netting	(108)	(63)
Resale agreements and securities borrowing, collateral received	(21,589)	(22,812)
Resale agreements and securities borrowing, net amount	388	650
Total, net amounts of assets presented in statement of condition	30,869	28,302
Total, counterparty netting	(108)	(63)
Total, collateral received	(22,034)	(23,217)
Total, net amount	$ 8,727	$ 5,022